MySQL基础-创建数据库和表
显示数据库一览 show databases; (SQL命令本身不区分大小写)
mysql> show databases;
Database
information_schema
mysql
test
小结：information_schema数据库又称信息架构，管理从表开始的数据库组成信息，以及用户管理信息的检索专用的数据库。确认这些数据库内容就可以掌握现在数据库的状态。不可在mysql和information_shema数据库中保存用户经常使用的数据。最后的test数据库是测试用的数据库，安装mysql会自动创建test数据库，数据库本身是空的。
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MySQL: How to avoid String Data Types common mistakes?May 13, 2025 am 12:09 AMToavoidcommonmistakeswithstringdatatypesinMySQL,understandstringtypenuances,choosetherighttype,andmanageencodingandcollationsettingseffectively.1)UseCHARforfixed-lengthstrings,VARCHARforvariable-length,andTEXT/BLOBforlargerdata.2)Setcorrectcharacters
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